Operating method of vacuum processing system and vacuum processing system

ABSTRACT

A vacuum processing apparatus and method wherein a plurality of processing units are for conducting processing, a transfer processing unit is connected with the plurality of processing units for carrying wafers to the processing units, a transfer device is disposed in the transfer processing unit and carries the wafers and cassettes for containing the wafers, and a control unit is provided for conducting transfer control for transferring the wafers from respective cassettes to the transfer processing unit. The wafers are processed by using the plural processing units, and at least two of the cassettes are used. Parallel processing is conducted of applying same processing to the wafers contained on each of the cassettes by applying the same recipe and the wafers, after applying the parallel processing, are returned to the original cassette.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of U.S. application Ser. No. 09/535,753, filedMar. 27, 2000 now U.S. Pat. No. 6,714,832, which is a continuation ofU.S. application Ser. No. 08/925,190, filed Sep. 8, 1997, now U.S. Pat.No. 6,069,096, the subject matter of which is incorporated by referenceherein.

BACKGROUND OF THE INVENTION

The present invention relates to a method of operating a vacuumprocessing system including two or more processing units for processingwafers and a transferring unit for carrying the wafers, wherein thewafers are processed using at least two or more of the processing units;and, the invention further relates to a vacuum processing system forcarrying out the method.

A system including a plurality of processing chambers connected to acarrying chamber, for example, as disclosed in Japanese Patent Laid-openNo. 133532/1988, (hereinafter referred to as the first known method) ischaracterized in that, in a normal operating state, different wafers canbe simultaneously carried into and processed in separate processingchambers, or each wafer can be carried into and processed sequentiallyin two or more of the processing chambers.

Another method of operating a processing system, for example, asdisclosed in Japanese Patent Laid-open No. 274746/1991, (hereinafterreferred to as the second known method) is characterized in that, in aoperation wherein processing steps are performed simultaneously throughprocessing chambers along two routes, if a processing chamber locatedalong one route is undergoing maintenance work, processing chamberslocated along the other route are temporarily used for all of theprocessing steps to be performed along the two routes.

Thus, there has been known heretofore:

a system in which wafers are subjected to a plurality of processingsteps in a vacuum by carrying wafers into two or more processingchambers through a carrying passage in a vacuum atmosphere andsubjecting the wafers to processing steps inherent to the individualprocessing chambers; a method of carrying wafers into the processingchambers; and a method wherein maintenance work is performedsimultaneously with the usual wafer processing.

The first known method, described in Japanese Patent Laid-open No.133532/1988, however, has failed to examine a situation in which aprocessing chamber becomes inoperable because of a failure or the likeduring an operation using two or more processing chambers along aprocessing route, to suggest that the processing should be continuedunder such a condition using the remaining operable processing chambers,or to consider ways of recovery of the inoperable processing chamber.

The first known method also has failed to consider a method andprocedure in which, if there is a processing chamber which is requiredto be repaired at the time of start of an operation, the system canstill be operated using only the remaining operable processing chambers.

The first known method also has failed to consider a method andprocedure in which, during an operation using two or more processingchambers along a processing route, when the operation is temporarilydiscontinued, a process interruption using as the processing route aprocessing chamber not normally used for the processing route prior tothe operation being discontinued is carried out in priority, and whereinthe processing which was temporarily discontinued is restarted aftertermination of the process interruption.

The first known method also has failed to consider, during an operationusing two or more of the processing units as a processing route, thesituation wherein an actuating instruction is supplied to apparatuses ina processing unit not currently used for the processing route from thepoint of view of securing a required level of safety of an operator whenan auxiliary operating unit spaced from a main operating unit suppliesthe actuating instruction to the apparatuses in the processing chambernot used in the processing route for the operation.

On the other hand, the second known method, described in Japanese PatentLaid-open No. 274746/1991, has failed to consider a manner of securingthe safety of the operator against a processing gas flowing due to “awrong operation” or electric shock due to improper operation of adischarging power supply when maintenance work for exchange of a targetor the like is performed by an operator standing on the side ofcomponents of the working system while the usual wafer processing isbeing performed.

Thus, although the known methods have examined the operation performedin a state wherein processing chambers are operable and in a state wherea processing chamber which needs to be repaired is initially omittedbefore start of operation, they have failed to consider operation in astate wherein a processing chamber become inoperable during processingdue to occurrence of an abnormal state, a process interruption, atemporarily discontinued state of operation and re-start of operationfrom the discontinued state, and actuation and utilization of aprocessing chamber not used for the processing route during operation.Accordingly, the known methods have failed to consider a method ofoperating a system, including processing chambers of the same kind whichare connected to each other, wherein, when a processing chamber becomesinoperable, the operation is continued using the remaining operableprocessing chambers. As a result, the previously disclosed methods havea poor working efficiency.

Further, the known methods have failed to consider ways of securing thesafety of an operator in the case where recovery of an abnormalprocessing chamber or periodic maintenance work is performedsimultaneously with the usual operation of normally processing wafers.

SUMMARY OF THE INVENTION

The present invention has been made to avoid the problems inherent inthe known methods.

Thus, a first object of the present invention is to provide a method ofoperating a vacuum processing system, including two or more ofprocessing units for processing wafers and a transferring unit fortransferring the wafers, in which the wafers are processed using atleast two or more of the processing units, wherein the system can becontinuously operated even when one of the processing units becomesinoperable because of a failure or the like during operation, using theremaining processing units to form a processing route, and to provide avacuum processing system for carrying out the method.

A second object of the present invention is to provide a method of thetype described, wherein, when a processing unit requires repair, thesystem can be operated using only the remaining operable processingchambers, and to provide a vacuum processing system for carrying out themethod.

A third object of the present invention is to provide a method of thetype described, which is capable of temporarily discontinuing theprocessing operation and re-starting the processing operation from thediscontinued state; and temporarily discontinuing the processingoperation, carrying out a process interruption using as the processingroute a processing chamber which has not used in the processing route ofthe processing operation prior to the operation being discontinued, andrestarting the temporarily discontinued operation after termination ofthe process interruption, and to provide a vacuum processing systemcapable of carrying out the method.

A fourth object of the present invention is to provide a method of thetype described, which, during operation of two or more of the processingchambers as a processing route, operates to issue an actuatinginstruction to apparatuses in a processing chamber not used for theprocessing route in such a way to secure the safety of the operator inthe case where the actuating instruction is supplied to the apparatusesof the processing chambers not used for the processing route,particularly, by an auxiliary operating unit spaced from a mainoperating unit, and to provide a vacuum processing system for carryingout the method.

A fifth object of the present invention is to provide a method of thetype described, which is capable of securing the safety of an operatorin the case where recovery work for an abnormal processing chamber orperiodic maintenance work is performed simultaneously with the usualoperation of normally processing wafers, thereby improving the workingefficiency of the system, while achieving an increased safety, and toprovide a vacuum processing system for carrying out the method.

To achieve the above objects, according to the present invention, thereis provided a processing system including: an operational informationsignal generating device provided in each processing unit for generatingan operational information signal indicating an operable or inoperablestate of the processing unit; an operational information signal storingdevice for storing operational information signals; and a system controldevice for continuously operating the system using operable ones of theprocessing units, without use of an inoperable processing unit, on thebasis of the operational information signals.

According to a method of operating the processing system of the presentinvention, when a processing unit becomes inoperable because of afailure or the like during operation, operation of the system istemporarily discontinued, and it is judged by an operator whether or notthe operation is to be continued. If it is decided that the operationshould be continued, the operation can be continued using the remainingoperable processing units.

According to the present invention, in the case where an operation isstarted in a state a processing unit requires repair or maintenance uponstart of operation, the system can be operated using the remainingoperable processing units, without use of the processing unit whichrequires repair or maintenance upon the start of operation.

To further achieve the above objects, according to the presentinvention, there is provided a method of operating a vacuum processingsystem and a vacuum processing system therefor, which are intended tosecure the safety of an operator by providing a function wherein an airline for driving an air operation valve of each gas line is cut off(such as by use of a manually opened/closed valve) for preventingoccurrence of the flow of a processing gas due to improper operation inthe case where recovery work for an abnormal processing chamber orperiodic maintenance work is performed simultaneously with the usualoperation for normally processing wafers, and also by providing afunction wherein, for example, an ON/OFF breaker for each power supplyline, is used for cutting off a power supply connected to a dischargingpower unit for preventing electric shock due to improper actuation ofthe discharging power supply during the recovery or maintenance work.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of one embodiment of a vacuum processingsystem according to the present invention;

FIG. 2 is a schematic diagram of another embodiment of the vacuumprocessing system according to the present invention;

FIG. 3 is a flow diagram showing a cleaning operation according to thepresent invention;

FIG. 4 is a block diagram showing a control configuration of a systemcontrol device provided in the vacuum processing system shown in FIG. 1;

FIG. 5 is a diagram showing operational information signals of thesystem control device provided in the vacuum processing system shown inFIG. 1;

FIG. 6 is a diagram showing processing order information of the systemcontrol device provided in the vacuum processing system shown in FIG. 1;

FIG. 7 is a flow chart showing automatic operation by the system controldevice provided in the vacuum processing system shown in FIG. 1;

FIG. 8 is a flow chart showing the details of the flow of automaticoperation shown in FIG. 7;

FIG. 9 is a flow diagram showing an operational state upon re-start ofautomatic operation after generation of an abnormal state in the vacuumprocessing system shown in FIG. 1;

FIG. 10 is a flow diagram showing an operational state in whichprocessing units are separated during automatic operation in the vacuumprocessing system shown in FIG. 1;

FIG. 11 is a flow diagram showing a change in operating state uponprocessing of a pilot cassette during automatic operation in the vacuumprocessing system shown in FIG. 1;

FIG. 12 is a schematic diagram showing separation of processing units inthe vacuum processing system;

FIG. 13 is a flow chart showing operational interlocking between a maincontrol unit and an auxiliary operation unit; and

FIG. 14 shows Table 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the present invention will be described withreference to FIGS. 1 to 14.

Referring to FIG. 1, there is shown an example of a processing systemrepresenting one embodiment of the present invention. The processingsystem includes four processing units, a transferring unit on which theprocessing units are mounted, and an atmospheric carrier disposed infront of a main body of the system. In this system, cassettes forsupplying wafers into the processing units are disposed in theatmospheric carrier, and the wafers are taken out of the cassettes oneby one, carried into the processing units, and processed in theprocessing units. It is to be noted that four or more processing unitsmay be mounted on the transferring unit. The transferring unit,indicated by reference numeral 1, is adapted to carry each of the wafersfrom a load lock chamber into each of the processing units on the basisof a wafer carrying schedule and to carry a wafer which has beenprocessed in one processing unit to the next processing unit, andfinally to carry a wafer which has been processed in all of theprocessing units into an unload lock chamber. The processing units areindicated by reference numerals 2-1 to 2-4. Here, the processing stepsinclude all of the typical wafer processing steps, such as etching,post-treatment, film formation, sputtering, CVD and washing. The loadlock chamber, indicated by reference numeral 3, is adapted to carrywafers from the atmospheric carrier into the transferring unit. Theunload lock chamber, indicated by reference numeral 4, is adapted tocarry wafers from the processing units into the atmospheric carrier. Theatmospheric carrier, indicated by reference numeral 6, is used formounting cassettes containing wafers. The cassettes, indicated generallyby reference numeral 7, include cassettes containing product wafers anda cassette containing cleaning wafers. Reference numeral 5 indicates avacuum robot provided in the transferring unit for carrying wafers, andreference numeral 8 indicates an atmospheric robot for taking wafers outof the cassettes in the atmospheric carrier, inserting them into theload lock chamber 3, and for returning the wafers in the unload lockchamber 4 to the original cassette.

In the usual operation, an operator sets the cassette 7-1 (or 7-2)containing product wafers and the cassette 7-3 containing cleaningwafers in the atmospheric carrier 6. An operational condition of thesystem is set using a display device 13 and an input device 14 and aninstruction for start of operation is given by the operator. As theoperation is started, wafers are carried into the processing units 2-1,2—2, 2-3 and/or 2-4 to be processed and returned to the originalcassette after processing. When the wafers in the cassette are allprocessed, a buzzer (not shown) is actuated to inform the operator ofthe need for recovering the cassette. The cassette is thus removed bythe operator.

After termination of processing with respect to the cassette orcassettes containing product wafers, the cleaning wafer is carried fromthe cassette 7-3 into the processing units 2-1 to 2-4, followed bycleaning of the processing units using the cleaning wafer, after whichthe cleaning wafer is returned to the cassette 7-3. The cleaning can beperformed by sequentially carrying one cleaning dummy wafer successivelyinto the processing unit 2-1 to 2-4, or by simultaneously carrying fourcleaning dummy wafers into the respective processing units 2-1 to 2-4.Although the cleaning is performed by carrying a cleaning dummy waferfrom the cassette 7-3 into the processing units 2-1 to 2-4 aftertermination of processing of the cassette or cassettes containing theproduct wafers, the cleaning may be performed without carrying thecleaning dummy wafer into the processing units 2-1 to 2-4. In additionto the cleaning performed after termination of processing of the productwafers contained in one cassette as described above, the cleaning can beperformed by carrying the cleaning dummy wafer from the cassette 7-3into the processing units 2-1 to 2-4 each time a specific number of theproduct wafers have been processed. However, the cleaning may beperformed without carrying the cleaning dummy wafer from the cassette7-3 into the processing units 2-1 to 2-4 each time a specific number ofthe product wafers are processed. In addition, the cleaning can beperformed by carrying the cleaning dummy wafer from the cassette 7-3into the processing units 2-1 to 2-4 after a specific number ofcassettes containing product wafers are processed.

The above wafer processing can be performed after aging without carryingthe cleaning dummy wafer from the cassette 7-3 into the processing units2-1 to 2-4 before start of processing the cassette containing productwafers. The above wafer processing can be also performed after carryingthe cleaning dummy wafer from the cassette 7-3 into the processing units2-1 to 2-4 before start of processing the cassette containing productwafers, followed by aging for a specific number of the wafers, and thenreturning the dummy wafer into the cassette 7-3.

It is to be noted that the cleaning is performed for removingcontaminants in a processing unit, and the aging is performed forreturning the state of the interior of a processing unit to a waferprocessing state before wafer processing.

The processing route as one of the operational conditions may be set byarranging symbols indicating processing units in the processing order ofwafers. The processing orders of wafers are shown as operating modes inTable 1 of FIG. 14.

In the following description of the operating mode, it is assumed thatthe same processing (etching in this embodiment) is performed in theprocessing units 2—2 and 2-3, and the same processing (post-treatment inthis embodiment) is performed in the processing units 2-1 and 2-4, sothat each wafer is subjected to etching in the processing unit 2—2 or2-3 and subsequently to post-treatment in the processing unit 2-1 or2-4. In the operation of this embodiment, it is also assumed that afterproduct wafers in one cassette are processed, a cleaning operation isperformed by carrying the cleaning wafer from the cassette 7-3 to theprocessing unit 2-3 (or 2—2) and to the processing unit 2-4 (or 2-1). Inthe processing of some wafers, only etching may be performed.

(1) Parallel Operation of One Cassette/One Recipe

In this operation, wafers to be processed in the same processingcondition (hereinafter referred to as “a recipe”) are sequentially takenfrom the lowermost or uppermost stage of a cassette, carried from thecassette into the processing units by the transferring unit, andprocessed in the processing units. Here, wafers are processed usingroutes A and B. In the route A, a wafer is subjected to etching in theprocessing unit 2—2 and to post-treatment in the processing unit 2-1,and is returned to the original cassette. In the route B, a wafer issubjected to etching in the processing unit 2-3 and to post-treatment inthe processing unit 2-4, and is returned to the original cassette.

The processing order in this embodiment is determined by a combinationof the routes A and B.

-   -   route A: cassette 7-1→processing unit 2—2→processing unit        2-1→cassette 7-1    -   route B: cassette 7-1→processing unit 2-3→processing unit        2-4→cassette 7-1

The processing order is not limited thereto, but also may be determinedby the following combination:

-   -   route C: cassette 7-1→processing unit 2—2→processing unit        2-4→cassette 7-1    -   route D: cassette 7-1→processing unit 2-3→processing unit        2-1→cassette 7-1

In the above processing order, the first wafer is processed along theroute A; the second wafer is processed along the route B; and the thirdwafer and the wafers subsequent thereto are similarly alternatelyprocessed along the routes A and B. After the final wafer is carriedfrom the cassette 7-1 (see FIG. 3A), the cleaning wafer is carried fromthe cassette 7-3 into the processing unit 2-3, to clean the processingunit 2-3 (see FIG. 3B). After the final wafer in the processing unit 2—2has been carried into the processing unit 2-1, a cleaning wafer iscarried from the cassette 7-3 into the processing unit 2—2, to clean theprocessing unit 2—2. After termination of cleaning of the processingunit 2-3, the cleaning wafer is carried from the processing unit 2-3into the processing unit 2-4, to clean the processing unit 2-4.

If a product wafer cassette 7-2 has been set in the carrier 6 by thistime, the cassette 7-2 is processed subsequent to termination ofprocessing of the cassette 7-1. That is, the first product wafer iscarried from the cassette 7-2 into the processing unit 2-3, and isprocessed therein (see FIG. 3C). After termination of cleaning in theprocessing unit 2-4, the cleaning wafer is returned to the cassette 7-3.If the cleaning in the processing unit 2—2 is terminated by this time,the cleaning wafer is carried from the processing unit 2—2 into theprocessing unit 2-1, to clean the processing unit 2-1. Then, the secondproduct wafer is carried from the cassette 7-2 into the processing unit2—2, and is processed therein (see FIG. 3D). When the wafers in thecassette 7-1 are all processed, a buzzer (not shown) is actuated toinform an operator of termination of processing the wafers in thecassette 7-1 and of the need to exchange the cassette. The cassette 7-2is also processed in the same processing order as that for the cassette7-1. When the wafers in the cassette 7-2 are all processed, the buzzeris actuated to inform an operator of termination of processing thewafers in the cassette 7-2 and of the need to exchange the cassette.Such an operational cycle will be repeated. The operation is terminatedby inputting an operation terminating signal at the main control unit11.

The processing is terminated in accordance with any one of the followingfive modes.

a) Stop the Wafer Supply: Taking wafers out of the cassette in thecourse of processing is stopped (in the case of an operation using twocassettes as one lot, taking wafers out of the designated cassette isstopped).

b) Stop the Cassette Supply: Processing of all wafers in a cassette inthe course of processing is continued until all wafers therein have beenprocessed, and thereafter processing of another cassette which has beenmounted by that time is prevented (in the case of an operation using twocassettes as one lot, processing of all wafers in the designatedcassette is continued until all wafers therein have been processed, andthereafter processing of the other cassette which has been mounted bythat time is prevented).

c) Stop of Cycle: the operating cycle is stopped directly after thepresent actions, such as processing, exhaust, leak, and carrying areterminated.

d) Temporary Stop of Processing Unit: operation of a designatedprocessing unit is stopped after the present processing is terminated.In this case, the operation can be re-started from the temporary stoppedstate by inputting an operation re-start signal. Only the processingunit concerned can be manually re-started.

e) Immediate Stop: all of the actions in the course of operation areimmediately stopped.

2) Parallel Operation of Two Cassette/One Recipe

In this operation, similar to the above “parallel operation of onecassette/one recipe”, wafers to be processed in the same processingcondition (or recipe) are sequentially taken from the lowermost oruppermost stage of a cassette, carried from the cassette into theprocessing units by the transferring unit, and processed in theprocessing units. This operation, however, is different from the“parallel operation of one cassette/one recipe” in terms of theprocessing order in which the wafers are taken out of the cassettes andcarried into the processing units by the transferring unit.

For the “parallel operation of one cassette/one recipe”, wafers aresequentially taken out of the same cassette, carried into the processingunits by the transferring unit, and processed in the processing units;and, after termination of processing of all of the wafers in thecassette, wafers in the next cassette are started to be processed. Onthe contrary, in this “parallel operation of two cassette/one recipe”,wafers are alternately taken out of the two cassettes 7-1 and 7-2,carried into respective processing units by the transferring unit, andare processed in the respective processing units. As in the “paralleloperation of one cassette/one recipe”, wafers are processed along theroutes A and B. In the route A, a wafer is subjected to etching in theprocessing unit 2—2 and to post-treatment in the processing unit 2-1 andis returned to the original cassette. In the route B, a wafer issubjected to etching in the processing unit 2-3 and to post-treatment inthe processing unit 2-4 and is returned to the original cassette. Theroutes C and b in the above “parallel operation of one cassette/onerecipe” also may be adopted in this “parallel operation of twocassette/one recipe”.

Specifically, in this operation, the first wafer is taken out of thecassette 7-1 and is processed along the route A; the second water istaken out of the cassette 7-2 and is processed along the route B; andthe third wafer and the wafers subsequent thereto are similarlyalternately taken out of the cassettes 7-1 and 7-2 and are processedalong the routes A and B. After termination of processing of all of thewafers in the cassette 7-1 or 7-2, a buzzer (not shown) is actuated toinform an operator of termination of processing of the cassette 7-1 (or7-2) and to the need to exchange the cassette. Until the terminatedcassette is replaced with a new cassette, only wafers in the othercassette are continuer to be processed. When the new cassette ismounted, wafers are once again alternately taken out of the cassettes7-1 and 7-2, carried into the processing units by the transferring unit,and processed in the processing units. The same operating cycle will berepeated thereafter. The operation is terminated by inputting anoperation terminating signal at the main control unit 11. Theterminating modes are the same as those in the “parallel operation ofone cassette/one recipe”. The cleaning may be performed in the samemanner as that described in the item (1) “Parallel Operation of OneCassette/One Recipe”.

3) Parallel Operation of Two Cassettes/Two Recipes

In this operation, since the wafer processing recipe for the cassette7-1 is different from that for the cassette 7-2, the processing timerequired for processing a wafer may sometimes differ for each processingunit. In this case, the carrying of wafers from the cassettes 7-1 and7-2 is not alternately performed, but is performed in such a manner thatafter a wafer is processed in one processing unit and is carried to thenext processing unit, the next wafer is carried into the formerprocessing unit. The other configuration is the same as that of the“parallel operation of two cassette/one recipe”. In addition, thecleaning may be performed in the same manner as that described in theitem (1) “Parallel Operation of One Cassette/One Recipe”.

4) Series Operation of One Cassette/One Recipe

In this operation, similar to the above “parallel operation of onecassette/one recipe”, wafers to be processed in the same processingcondition (or recipe) are sequentially taken from the lowermost oruppermost stage of a cassette, carried from the cassette into theprocessing units by the transferring unit, and processed in theprocessing units. This operation, however, is different from the“parallel operation of one cassette/one recipe” in terms of theprocessing route. In this “series operation of one cassette/one recipe”,wafers are processed along a route E in which each wafer is subjected toetching in the processing unit 2—2 (or 2-3), to etching in theprocessing unit 2-3 (or 2—2), and to post-treatment in the processingunit 2-1 (or 2-4), and is returned to the original cassette.

Specifically, the first wafer is processed along the route E, and thesecond wafer is processed along the same route E. Such an operationalcycle is repeated until the final wafer in the cassette is processed.After termination of processing of all of the wafers in the cassette7-1, a buzzer (not shown) is actuated to inform an operator oftermination of processing of the cassette 7-1 and of the need toexchange the cassette. If the cassette 7-2 is mounted by that time,wafers in the cassette 7-2 are subsequently processed in the sameprocessing order as that for the wafers in the cassette 7-1 Aftertermination of processing of all of the wafers in the cassette 7-2, thebuzzer (not shown) is actuated to inform an operator of termination ofprocessing of the cassette 7-2 and of the need to exchange the cassette.If the next cassette 7-1 is mounted by that time, wafers in the cassette7-1 are subsequently processed. Such an operational cycle will berepeated thereafter. The operation is terminated by inputting anoperation terminating signal at the main control unit 11. Theterminating modes are the same as those in the “parallel operation ofone cassette/one recipe In addition, the cleaning may be performed inthe same manner as that described in the item (1) “Parallel Operation ofOne Cassette/One Recipe”.

Although the operating methods 1) to 4) have been described, such adescription is for illustrative purposes only, and it is to beunderstood that many changes in operating method may be made bysubjecting a combination of cassettes, recipes, and the kinds (paralleland series) of operation.

For maintenance of the system, the system can be operated by an operatorstanding on the system side using a display device 26 and an inputdevice 25 disposed in an auxiliary operation panel 22. The auxiliaryoperation panel 22, represented by a portable terminal (for example, anote type personal computer), can be carried near the system.Accordingly, the operator can make use of system information (forexample, ON/OFF information of input/output bit, error information,etc.) displayed on the display device 26 while visually observing thesystem condition during maintenance of the system. That is, theauxiliary operating panel 22 is effective to improve the operability ofthe maintenance work. The auxiliary operation panel 22, which has thesame function as that of the main control unit 11, is further providedwith a wrong operation preventive function for securing the safety ofthe operator. Specifically, the operating right for the system may beshifted to the auxiliary operation panel 22, in the event of which themain control unit 11 is not allowed to operate the system, and viceversa.

FIG. 2 is a view showing one example of another embodiment of theprocessing system of the present invention. In this system, fourprocessing units are mounted on a transferring unit, and a cassette forsupplying wafers into the processing units is set in a load lock chamber3A provided in a main body of the system, wherein wafers are taken outof the cassette one by one, carried into the processing units by thetransferring unit, and processed in the processing units. In addition,four or more processing units may be mounted on the transferring unit.

In the configuration of the system of this embodiment, the atmosphericcarrier 6 in which cassettes containing wafers are set and theatmospheric robot 8 are omitted from the configuration shown in FIG. 1.In other words, the function and configuration of this system are thesame as those of the system shown in FIG. 1, except that the supply ofwafers from a cassette is performed in the load lock chamber 3A and thereturn of the wafers to the cassette is performed in an unload lockchamber 4A. The cleaning is performed by setting a cassette containingcleaning wafers in the load lock chamber 3A (or unload lock chamber 4A),carrying the cleaning wafer into the processing units 2-1 to 2-4,cleaning the processing units using the cleaning wafer, and returningthe cleaning wafer to the original cassette. The operation modes in thisembodiment are as follows:

(1) Parallel Operation of One Cassette/One Recipe

In this operation, wafers to he processed in the same processingcondition (recipe) are sequentially taken from the lowermost oruppermost stage of a cassette, carried from the cassette into theprocessing units by the transferring unit, and processed in theprocessing units. The wafers are processed using routes A and B. In theroute A, a wafer is subjected to etching in the processing unit 2—2 andto post-treatment in the processing unit 2-1, and is returned to theoriginal cassette. In the route B, a wafer is subjected to etching inthe processing unit 2-3 and to post-treatment in the processing unit2-4, and is returned to the original cassette.

The processing order in this embodiment is determined by a combinationof the routes A and B.

-   -   route A: cassette 7-1A in load lock chamber 3A→processing unit        2—2→processing unit 2-1→cassette 7-1 in unload lock chamber 4A    -   route B: cassette 7-1A in load lock chamber 3A→processing unit        2-3→processing unit 2-4→cassette 7-2A in unload lock chamber 4A

The processing order is not limited thereto, but also may be determinedby the following combination:

-   -   route C: cassette 7-1A in load lock chamber 3A→processing unit        2—2→processing unit 2-4→cassette 7-2A in unload lock chamber 4A    -   route D: cassette 7-1A in load lock chamber 3A→processing unit        2-3→, processing unit 2-1→cassette 7-2A in unload lock chamber        4A

In the above processing order, the wafers which have been processed arereturned to the cassette 7-2A in the unload lock chamber 4A; however,they can be returned to the cassette 7-1A, out of which they have beentaken, in the load lock chamber 3A.

In connection with this embodiment, there will be described an examplein which wafers taken out of a cassette 7-1A in the load lock chamber 3Aare processed along the parallel routes A and B, and are returned to aninitially empty cassette 7-2A in the unload lock chamber 4A.Specifically, the first wafer is processed along the route A; the secondwafer is processed in the route B; and the third wafer and the waferssubsequent thereto are similarly alternately processed in the routes Aand B. After termination of processing of all of the wafers in thecassette 7-1A in the load lock chamber 3A, a buzzer (not shown) isactuated to inform an operator of termination of processing the cassette7-1A in the load lock chamber and the cassette 7-2A in the unload lockchamber 4A and of the need to exchange the cassettes. Next, a cassettecontaining new wafers is set in the load lock chamber 3A and an emptycassette is set in the unload lock chamber 4A. The operating cycle willbe repeated thereafter. The operation is terminated by inputting anoperation terminating signal at the main control unit 11. Theterminating modes are the same as those in the “parallel operation ofone cassette/one recipe” in the previous embodiment.

2) Parallel Operation of Two Cassette/One Recipe

In this operation, wafers to be processed in the same processingcondition (or recipe) are sequentially taken from the lowermost oruppermost stage of a cassette, carried from the cassette into theprocessing units by the transferring unit, and processed in theprocessing units.

For the above “parallel operation of one cassette/one recipe”, wafersare sequentially taken out of the same cassette, carried into theprocessing units by the transferring unit, and processed in theprocessing units; and, after termination of processing of all of thewafers in the cassette, processing of wafers in the next cassette isstarted. However, in this “parallel operation of two cassette/onerecipe”, wafers are alternately taken out of the cassette 7-1A in theload lock chamber 3A and the cassette 7-2A in the unload lock chamber4A, carried into the processing units by the transferring unit, and areprocessed in the processing units. As in the “parallel operation of onecassette/one recipe”, the wafers are processed along the routes A and B.In the route A, a wafer is subjected to etching in the processing unit2—2 and to post-treatment in the processing unit 2-1 and is returned tothe original cassette. In the route B, a wafer is subjected to etchingin the processing unit 2-3 and to post-treatment in the processing unit2-4 and is returned to the original cassette. The routes C and D in theabove “parallel operation of one cassette/one recipe” also may beadopted in this “parallel operation of two cassette/one recipe”.

Specifically, the first wafer is taken out of the cassette 7-1A in theload lock chamber 3A and processed along the route A, and the secondwafer is taken out of the cassette 7-2A in the unload lock chamber 4Aand processed along the route B. And, this same operating cycle will berepeated until the final wafer in either of the cassettes 7-1A and 7-2Ais processed. After termination of processing of all of the wafers inthe cassette 7-1A in the load lock chamber 3A or the cassette 7-2A inthe unload lock chamber 4A, the buzzer is actuated to inform an operatorof termination of processing of the wafers in the cassette in the loadlock chamber 3A or in the unload lock chamber 4A and of the need toexchange the cassette. Until the terminated cassette is removed and anew cassette is set, only wafers in the other cassette continue to beprocessed. When the new cassette is set, wafers are alternately takenout of the cassette in the load lock chamber 3A and the cassette in theunload lock chamber 4A, carried into the processing units by thetransferring unit, and processed in the processing units. The sameoperating cycle will be repeated thereafter. The operation is terminatedby inputting an operation terminating signal at the main control unit11. The operating modes are the same as those in the above “paralleloperation of one cassette/one recipe”.

3) Parallel Operation of Two Cassettes/Two Recipes

In this operation, the wafer processing recipe for the cassette 7-1A inthe load lock chamber 3A may be sometimes different from the waferprocessing recipe for the cassette 7-2A in the unload lock chamber 4A.In this case, the carrying of wafers from the cassettes 7-1A and 7-2A isnot alternately performed, but is performed in such a manner that, aftera wafer is processed in a processing unit and is carried to the nextprocessing unit, the next wafer is carried into the former processingunit. The other features are the same as those of the above “paralleloperation of two cassette/one recipe”. In addition, the cleaning may beperformed in the same manner as that described in the item (1) “ParallelOperation of One Cassette/One Recipe”.

4) Series Operation of One Cassette/One Recipe

In this operation, similar to the above “parallel operation of onecassette/one recipe”, wafers to be processed in the same processingcondition (or recipe) are sequentially taken from the lowermost oruppermost stage of a cassette, carried from the cassette into theprocessing units by the transferring unit, and processed in theprocessing units. This operation, however, is different from the“parallel operation of one cassette/one recipe” in terms of theprocessing route. In this “series operation of one cassette/one recipe”,wafers are processed along a route E in which each wafer is subjected toetching in the processing unit 2—2 (or 2-3), to etching in theprocessing unit 2-3 (or 2—2), and to post-treatment in the processingunit 2-1 (or 2-4), and is returned to the original cassette.

In connection with this embodiment, there will be described an examplein which wafers taken out of the cassette 7-1A in the load lock chamber3A are processed along the route E and are returned to the cassette 7-2Ain the unload lock chamber 4A. The first wafer is processed along theroute E, and the second wafer is also processed along the same route E.Such an operational cycle will be repeated until the final wafer in thecassette 7-1A is processed. After termination of processing of all ofthe wafers in the cassette 7-1A, the buzzer (not shown) is actuated toinform an operator of termination of processing the cassette 7-1A in theload lock chamber 3A and the cassette 7-2A in the unload lock chamber7-2A and of the need to exchange the cassettes. Next, a cassettecontaining new wafers is set in the load lock chamber 3A and an emptycassette is set in the unload lock chamber 4A. Thus, the above operatingcycle will be repeated thereafter. The operation is terminated byinputting an operation terminating signal at the main control unit 11.The terminating modes are the same as those in the “parallel operationof one cassette/one recipe”.

FIG. 4 is a diagram showing the configuration of the main control unit11 of the system. In this embodiment, the main control unit for entirelycontrolling the system is mounted in the transferring unit 1; however,it may be mounted separately from the transferring unit 1. The displaydevice 13 and the input device 14 also may be provided separately fromthe main control unit. It is to be noted that, in the figure, there areillustrated only essential portions as control device, with input/outputcontrol portions (DI/O, AI/O) necessary for operation of the systembeing omitted. Reference numeral 16 indicates a processing orderinformation storing device for storing processing orders of wafers inthe vacuum processing system, which storing device is represented by aRAM (Random Access Memory). Data as to the processing orders of thewafers, which are inputted by an operator using the display device 13and the input device 14 before start of operation, are stored in theprocessing order information storing device 16. Reference numeral 17indicates an operational information signal storing device for storingoperational information signals indicating operable/inoperable states ofthe processing units 2-1 to 2-4, which storing device is represented bya RAM. The display device 13 is used for displaying an operationalstate, setting the content of the operating condition, and instructionof the start/termination of operation, which display device isrepresented by a CRT. The input device 14 is used for inputting anoperational condition, instruction for start of operation, processingcondition, and action for maintenance, which input device is representedby a keyboard. Reference numeral 15 indicates a system control devicefor judging operation information signals indicating operable/inoperablestates of the processing units 2-1 to 2-4 and for storing a processingorder in which, when any one of the processing units 2-1 to 2-4 becomesinoperable during automatic operation, the operation is continued usingthe remaining operable processing units, which control device isrepresented by a ROM (Read Only Memory). Reference numeral 12 indicatesa central control device for controlling the units 13 to 17, whichcontrol device is represented by a CPU (Central Processing Unit). Theprocessing units 2-1 to 2-4 are used for carrying out wafer processingsteps, such as etching, post-treatment, film formation, sputtering, CVD,and washing. Reference numerals 19-1 to 19-4 indicate operationalinformation signal generating device for generating operationalinformation signals indicating operable/inoperable states of theprocessing units 2-1 to 2-4. In this embodiment, the units 19-1 to 19-4are provided in the processing units; however, they may be provided atany portions of the apparatus. The units 19-1 to 19-4 generateoperational information signals by the use of:

1) cut-off signals of power supplies for the processing units;

2) operation switching signals (for example, turn on/off of switches)for setting operable/inoperable states of the processing units; and

3) input information inputted by an operator as operational controlsignals indicating operable/inoperable states of the processing units.

Reference numerals 20 and 21 indicate communication devices forconnecting the main control unit 11 to the auxiliary operation panel 22.The auxiliary operation panel 22 includes an input device 25 and adisplay device 26; a terminal control device 24 for storing processingorders for controlling the terminal function at the auxiliary operationpanel; and a central control device 23 for controlling the devices 21and 24 to 26, which central control device is represented by a CPU(Central Processing Unit).

FIG. 5 is a diagram showing operational information signals. Informationindicating an operable/inoperable state of each processing unit isstored. In the example shown in FIG. 5, the operable state is indicatedby “1” and the inoperable state is indicated by “0”. However, theoperable/inoperable states may be indicated by other signal statescapable of distinguishing the operable/inoperable states from eachother. The information is created on the basis of a signal supplied fromeach of the operational information signal generating device 19-1 to19-4, and is stored in the operational information signal storing device17.

FIG. 6 is a diagram showing information as to the processing order. Theprocessing order setting information is set, as one of the operatingconditions, by an operator using the display device 13 and the inputdevice 14 before start of operation. The information is stored in theprocessing order information storing device 17.

FIG. 7 is a flow chart showing operating steps of the system. At step30, an operator judges before the start of operation whether or not oneof the processing units 2-1 to 2-4 is inoperable because of a failure,or whether one of the processing units can not be operated formaintenance (or plasma cleaning). If the result is yes, the process goeson to step 32, at which the operational information signals forindicating operable/inoperable states of the processing units 2-1 to 2-4(see FIG. 5) are switched using the operational information signalgenerating device 19-1 to 19-4. The switching of the operationalinformation signals is performed as follows:

1) In the case of using a cut-off signal of the power supply of theprocessing unit, a solenoid switch of the processing unit is turned off.The cut-off signal thus generated is transmitted to the operationalinformation signal storing device 17 and is stored as the informationshown in FIG. 5.

2) In the case of using an operation switching signal (for example,turn-on/off of switch) for setting the operable or inoperable state ofthe processing unit, the switch allocated to the processing unit is setin the operable or inoperable state. The switching signal thusdetermined is transmitted to the operational information signal storingdevice 17 and is stored as the information shown in FIG. 5.

3) In the case of using information set by an operator as an operationalcontrol signal indicating the operable or inoperable state of theprocessing unit, the operator inputs the setting information allocatedto the processing unit using the input device 14.

The setting information (operational information signals) thusdetermined is transmitted to the operational information signal storingdevice 17 and is stored as the information shown in FIG. 5. After thesystem connection state is thus determined, the process goes on to step32 at which automatic operation is started. In addition, the processingorder for wafers is set as a product processing condition as follows:

1) The operation mode for wafers is selected to be one of “paralleloperation of one cassette/one recipe”, “parallel operation of twocassettes/one recipe”, “parallel operation of two cassettes/tworecipes”, and “series operation of one cassette/one recipe”.

2) The carrying route of wafers is set.

The parallel or series processing route is set using symbols of theprocessing units for each cassette. Typical examples are as follows. Itis to be noted that the processing routes for wafers can be variouslyset by the combination as described above.

2-1) Parallel Processing:

cassette 7-1: E1→A1, cassette 7-1: E2→A2

cassette 7-2: E1→A1, cassette 7-2: E2→A2

E1: processing unit 2—2, E2: processing unit 2-3

A1: processing unit 2-1, A2: processing unit 2-4

2-1) Series Processing

cassette 7-1: E1→E2→A1

cassette 7-2: E2→E1→A2

3) The processing condition (“process recipe”) is set for eachprocessing chamber.

After the product processing condition is thus set, automatic operationis started in step 34.

FIG. 8 is a flow chart of automatic operation of the system. Whenautomatic operation is started, it is judged at step 40 whether or notprocessing of all wafers to be processed has been carried out. If yes,the processing is terminated. If no, the process goes on to step 42, atwhich it is judged whether or not automatic operation can be performedwithout the occurrence of an abnormal state. If yes, that is, in thecase where there is no abnormal state, the process goes on to step 44 atwhich automatic operation is continued. If no, that is, in the casewhere there exists an inoperable processing unit, the process goes on tostep 70 at which it is judged by an operator whether or not automaticoperation can be continued without use of the inoperable processingunit. If no, that is, in the case where automatic operation cannot hecontinued, the process goes on to step 90 at which automatic operationof the system is stopped by the operator. If yes, that is, in the casewhere automatic operation can be continued, handling of a waferremaining in the inoperable processing unit or an associated apparatusis required to he examined. Specifically, in this case, the waferpossibly remains in the inoperable processing unit, on a hand of thevacuum robot, or in the load lock chamber or unload lock chamber. Tore-start automatic operation from the state that automatic operation istemporarily discontinued because an abnormal state occurs duringautomatic operation, the wafer remaining in the inoperable processingunit or the associated apparatus must be returned to the originalcassette. The reason for this is as follows: namely, since thecarrying/processing schedule for all of the wafers in the processingunits is established at the time of occurrence of the abnormal stateduring automatic operation, the schedule will become disrupted unlessthe wafer remaining in the inoperable processing unit or the associatedapparatus is returned to the cassette, with a result that re-start ofautomatic operation from the temporarily discontinued state becomesimpossible.

As another example, automatic operation for the normal wafers may bere-started from the temporarily discontinued state while the waferremaining in the abnormal processing unit or apparatus is not returnedto the original cassette, that is, left as it is. In this case, theremaining wafer is returned to the original cassette after terminationof automatic operation for the normal wafers. As a further example, thewafer information may be changed as if the remaining wafer was returnedinto the original cassette. For example, with the wafer remaining in theabnormal processing unit being left as it is, the wafer information ischanged as if the wafer was carried to the original cassette, andautomatic operation for the normal wafers (one lot) is re-started fromthe temporarily discontinued state. In this case, the remaining wafer isreturned to the original cassette after termination of automaticoperation for the normal wafers. The wafer remaining in the inoperableprocessing unit will be handled in accordance with the flow chart ofFIG. 8.

At step 72, it is judged whether or not a wafer exists in the inoperableprocessing unit. If yes, the process goes on to step 73, at which it isjudged whether or not automatic operation can be continued with thewafer remaining in the inoperable processing unit being left as it is.If yes, that is, in the case where automatic operation can be continuedwith the remaining wafer being left as it is, the process goes on tostep 77, at which the wafer information is changed as if the remainingwafer was carried into the original cassette. If no, that is, in thecase where automatic operation is not continued with the remaining waferbeing left as it is, the process goes on to step 74, at which it isjudged whether or not the remaining wafer is required to be etched. Ifyes, that is, in the case where an abnormal state occurs midway of theetching step, the process goes on to step 76, at which the remainingwafer is subjected to the remainder of the etching step. And, in step78, the remaining wafer is returned to the original cassette. Such aprocess is performed to help the wafer remaining in the abnormalprocessing unit as far as possible. If the wafer remains on a wafer handof the vacuum robot, or in the load lock chamber or unload lock chamber,it is returned to the original cassette (step 78) after performing theoperation necessary for the apparatus (exhaust/leak of the lock chamber,or carrying of wafer). In this way, the wafer in the inoperableprocessing unit, or the associated apparatus, undergoes a necessarymeasure and is returned to the original cassette, and then automaticoperation is restarted from the temporarily discontinued state. Withthis handling, the tracking information of the wafer in the abnormalprocessing unit or apparatus (for example, vacuum robot) becomes equalto that of a wafer which has been processed along the normal route.Thus, automatic operation can be re-started. After handling the waferremaining in the inoperable processing unit, the process goes on to step80, at which the operational information is switched using theoperational information signal generating device in the same manner asthat described in step 32 of FIG. 7. The process goes on to step 82 atwhich the abnormal state generation information is re-set, thuscontinuing automatic operation.

Next, there will be described automatic operation in the normal state.In step 44, the information stored in the processing order informationstoring device 16 is read out, and in step 46, the carrying route forthe next wafer is determined by comparing the information thus read outfrom the device 16 with the information stored in the operationalinformation signal storing device 17. The determined carrying route mayhave carrying route data for each wafer carried from the cassette, ormay be referred to a processing order information table preparedseparately from the processing order information storing device 16 whenthe wafer is carried. After the carrying route is determined, a wafer iscarried out of the cassette by the atmospheric robot (step 48), carriedinto the processing unit registered in the determined carrying route (atstep 50), and processed (step 52). In the case where an abnormal stateoccurs in the operation of carrying and processing wafers, theprocessing steps, which are allowed to be continued, are continued tocompletion, and then automatic operation is temporarily discontinued.For example, when an abnormal state occurs during etching of the N-thwafer, the etching step is continued until the etching of the N-th waferis terminated, and then automatic operation is temporarily discontinued.Also, in the case where, during the carrying of a wafer using the vacuumrobot 5, there occurs an abnormal state in a different processing step,the vacuum robot 5 continues to carry the wafer to a specific point, andthen automatic operation is temporarily discontinued. Then, abnormalstate generation information (not shown) indicating the generation of anabnormal state is stored, and thereafter, the temporarily discontinuedstate of the system is displayed on the display device 13 with thebuzzer (not shown) being actuated in order to inform an operator of thetemporarily discontinued state. After that, the process is returned tostep 42, at which the processing is performed under the specific flow.

FIG. 9 is a view showing re-start of automatic operation after theoccurrence of an abnormal state. The processing until re-start ofautomatic operation after an abnormal state occurs during the automaticoperation described with reference to FIG. 8 will be described.Referring to FIG. 9A, the system is operated in the “parallel operationof one cassette/one recipe” mode and with the following carrying routes:

cassette 7-1: E1→A1 and E2→A2

cassette 7-2: E1→A1 and E2→A2

Here, it is assumed that when the N-th wafer is subjected to etching inE2 and the (N−1)-th wafer is subjected to post-treatment in A1, anabnormal state occurs in E2 as shown in FIG. 9B. In this case, thepost-treatment of the (N−1)-th wafer in A1, which has been alreadyetched, is continued to completion, and thereafter automatic operationis temporarily discontinued without carrying the (N−1)-th wafer into theunload lock chamber 4. The N-th wafer in E2 where the abnormal stateoccurs is handled as described in steps 76 and 78 of FIG. 7. Withrespect to E2 and A2, the operational information is switched using theoperational information signal generating device as described in step 80of FIG. 8. Specifically, the operational information is switched inaccordance with any one of the operations 1), 2) or 3) described withreference to FIG. 7, so that the operational information of each of theprocessing units 3 (E2) and 4(A2) is set at “inoperable: 0” as shown inFIG. 5. Then, the abnormal state generation information is reset (seestep 80 in FIG. 8), to re-start automatic operation. After re-start ofautomatic operation, the (N−1)-th wafer in A2 is carried into the unloadlock chamber 4 as shown in FIG. 9C. The processing is continued using E1and A1 thereafter.

Next, with reference to the processing units 3 (E2) and 4 (A2) regardedas “inoperable: 0”, apparatuses in the processing units 4 (E2) and 4(A2)are actuated to search for the cause of the abnormal state using theauxiliary operation panel 22. For example, the action of the processingunit 3 (E2) is confirmed by performing a wafer pushing operation (notshown).

Next, there will be described a procedure in which the processing units3 (E2) and 4 (A2) regarded as “inoperable: 0” are returned to theprocessing route of wafers after the cause of the abnormal state is madeclear by the above operation. Specifically, automatic operation shown inFIG. 9C is temporarily discontinued, and the operating state is returnedto that shown in FIG. 9A by setting operable E2 and A2, which have beenseparated from the processing route.

Thus, the wafers can be operated on in the following carrying routes:

cassette 7-1: E1→A1 and E2→A2

cassette 7-2: E1→A1 and E2→A2

FIG. 10 is a view showing the operation of separating a processing unitfrom a processing route during automatic operation. Hereinafter, therewill be described an operation of re-starting automatic operation afterE2 and A2 are separated from a processing route of automatic operationdescribed with reference to FIG. 8. The operating route shown in FIG.10A is the same as that shown in FIG. 9A. That is, the system isoperated in the “parallel operation of one cassette/one recipe” mode inTable 1 of FIG. 14 and the following carrying routes:

cassette 7-1: E1→A1 and E2→A2

cassette 7-2: E1→A1 and E2→A2

Here, it is assumed that when the N-th wafer is subjected to etching inE2 and the (N−1)-th wafer is subjected to post-treatment in A1,instructions are given to stop operation of E2 and A2 as shown in FIG.10A by performing an operation stop action. In this case, the (N−1)-thwafer in A1 is returned to the original cassette after termination ofpost-treatment; and, the N-th wafer in A1 is carried into A2 aftertermination of etching, is subjected to post-treatment in A2, and isreturned to the original cassette after termination of post-treatment.Incidentally, since E2 and A2 are in the operation stop state, the(N+1)-th wafer and the wafers subsequent thereto continue to be operatedon using E1 and A1.

In the above example, E2 and A2 are separated from the processing routeduring automatic operation by issuing stop instructions through theoperation stop action; however, the stop instructions can be obtainedfrom detectors assembled in the processing units. As one example, whencontaminant monitors assembled in the processing units E2 and A2 detectthat monitored values are more than predetermined values, stopinstructions similar to those described above can be given to E2 and A2during automatic operation on the basis of the detected results.

The procedure for returning the separated processing units into theprocessing route is the same as that described with reference to FIG. 9.

FIG. 11 is a view showing processing of a pilot cassette, in which aprocess interruption is generated during automatic operation and theoriginal processing is re-started after termination of the interruption.During automatic operation described with reference to FIG. 8, specificprocessing units (E2 and A2 in this example) are separated from thepresent processing route, and the processing of a cassette (called apilot cassette) to be processed in a processing condition different fromthe present processing condition is interrupted and the pilot cassetteis processed using the separated units E2 and A2. After termination ofprocessing of the pilot cassette, the original automatic operation isre-started. Such a process interruption will be more clearly describedbelow. The operating route shown in FIG. 11A is the same as that shownin FIG. 9. That is, the system is operated in the “parallel operation ofone cassette/one recipe” mode in Table 1 of FIG. 14 and with thefollowing carrying route:

cassette 7-1: E1→A1 and E2→A2

cassette 7-2: E1→A1 and E2→A2

When the N-th wafer in the cassette 7-1 is subjected to etching in unitE2 and the (N−1)-th wafer in the cassette 7-1 is subjected to posttreatment in unit A1, automatic operation is discontinued for performingan emergency process interruption using units E2 and A2 as shown in FIG.11A. When stop instructions are given to units E2 and A2 by an operationstop action, the (N−1)-th wafer in unit A1 is returned to the originalcassette after termination of post-treatment, and the N-th wafer iscarried into unit A2 after termination of etching, is subjected topost-treatment, and is returned to the original cassette. Incidentally,since units E2 and A2 are in the operation stop state, the (N+1)-thwafer and the wafer subsequent thereto continue to be operated usingunits E1 and A1 (see FIG. 11C). During operation using units E1 and A1,the pilot cassette used for emergency process interruption using unitsE2 and A2 is replaced with the cassette 7-2, followed by start of theprocess interruption (see FIG. 11C), and the wafers which have beentaken out of the cassette 7-1 until that time are all processed andcarried into the cassette 7-1. At this time, processing for the wafersin the cassette 7-1 using units E1 and A1 is temporarily discontinued,and processing of wafers in the pilot cassette 7-2 for emergency processinterruption is started (see FIG. 11D). The wafers in the pilot cassette7-2 are sequentially processed in the order of E2→A2, and carried intothe pilot cassette 7-2. After termination of processing of the pilotcassette 7-2, termination of the interruption and re-start of operationfrom the temporarily discontinued state is set, and processing of wafersfrom the cassette 7-1, which has been discontinued, is re-started(returned to the state shown in FIG. 11C). Next, during operation in thestate shown in FIG. 11C, automatic operation is discontinued, and thenthe operating state is returned to that shown in FIG. 11A by settingoperable units E2 and A2, which have been separated from the processingroute. Thus, the system can be operated in the following processingroutes:

cassette 7-1: E1→A1 and E2→A2

cassette 7-2: E1→A1 and E2 A2

FIG. 12 shows air-line and power supply cutting off configurations ofthe vacuum processing system for the processing units. Each of theprocessing units 2-1 to 2-4 is provided with a manually operatedopened/closed valve for cutting off an air line for driving an airoperation valve for each processing gas, and a breaker for turningon/off a power supply, thereby cutting off the power supplied to adischarge power supply unit. In connection with this embodiment, therewill be described a “parallel operation of one cassette/one recipe” forprocessing wafers using the processing units 2-3 and 2-4 simultaneouslywith the performing of maintenance work for exchanging an electrode inthe processing unit 2-2. In addition, only the configurations of thoseof the processing units necessary for the description are illustrated inthe figure.

The operation of the system is performed along routes A and B (see theembodiment shown in FIG. 1). Here, since the processing unit 2—2 isundergoing maintenance work, the valve 29 for manually opening/closingthe air line for driving the air operation valve of the gas line in theprocessing unit 2—2 is closed, and the breakers 27 and 28 for powersupplied to the discharge power supply unit are turned off to cut offpower to the processing units 2—2 and 2-1. Thus, the system is operatedas shown in FIG. 7. Accordingly, even when an operation which allowsprocessing gas to flow in the processing unit 2—2 during maintenance iserroneously performed, the processing gas does not flow because the airline for driving the air operation valve for the gas line is cut off.Even when the discharge power supply is erroneously turned on, anoperator does not suffer from electric shock because the power suppliedto the discharge power supply unit is cut off. In this way, even whenthe usual water processing is performed simultaneously with themaintenance work for the system and apparatuses by an operator standingon the system side of the apparatuses of the working system, theoperator does not suffer from the processing gas flowing due to a wrongoperation and/or electric shock due to turn-on of the discharge powersupply. As a result, it is possible to secure the safety of theoperator.

FIG. 13 is a flow chart of interlocking operation between the maincontrol unit and an auxiliary operation panel, when the processing unit2—2 is operated using the auxiliary operation panel 22 during operationof the system shown in FIG. 1 by the main control unit 11.

If the operation right for the processing unit 2—2 is shifted from themain control unit 11 to the auxiliary operation panel 22 beforeoperation of the processing unit 2—2 by the auxiliary operation panel 22(step 102), the main control unit 11 cannot operate the processing unit2—2 until it receives the operating right (step 106). And, the auxiliaryoperation panel 22, when it receives the operating right for theprocessing unit 2—2 (step 104), then can operate the processing unit 22(step 108). After termination of the operation of the processing unit2—2 by the auxiliary operation panel 22 (step 110), the operating rightis shifted from the auxiliary operation panel 22 to the main operatingunit 11 (step 112), after which the auxiliary operation panel 22 cannotoperate the processing unit 2—2 (step 114). The main control unit 11,when it receives the operating right for the processing unit 11 (step116), then can operate the processing unit 11 (step 118). In this case,the main control unit 11 can operate all of the processing units (step120).

As described above, information concerning a processing unit which isinoperable because of a failure or the like, or a processing unit cannot he used because of repair or maintenance (including plasmacleaning), is stored in the operational information signal storingdevice 17, and the system control device allows operation of the systemon the basis of the information stored in the storing device 17. As aresult, a wafer is not carried in the processing unit which is set asinoperable. In the case of carrying out repair and maintenance of theinoperable processing unit and searching for the cause thereof,operations, such as plasma cleaning, gas line exhaust, lifting/loweringaction of a wafer pusher for maintenance work or the like, can beperformed on the side apart from the other apparatuses of the processingunit, simultaneously with automatic operation for processing wafers. Inthe case of performing operations for carrying out repair andmaintenance and searching for the cause of the abnormal state on theside of the apparatuses of the inoperable processing unit, the aboveauxiliary operation panel 22 is used. Incidentally, in the usualproduction line, the atmospheric carrier 6 shown in FIG. 1 is disposedon the clean room side and the transferring unit 1 and the processingunits 2-1 to 2-4 are disposed on the maintenance room side, and theclean room side is partitioned from the maintenance room side by apartition. Accordingly, in some cases, one of the sides can not besufficiently viewed from the other side. Also, the auxiliary operationpanel 22, which is connected to the main control unit 11, is usuallyoperated at a location spaced from the main control unit 11. In thesecases, if the system is allowed to be operated by the main control unit11 and the auxiliary operation panel 22, when the system is operatedusing the auxiliary operation panel 22 particularly on the maintenanceroom side, there is the possibility that an accident to the operatorwill occur. To prevent occurrence of such an accident, when an operation(for example, lifting/lowering action for pushing a wafer) is performedfor a processing unit using the auxiliary operation panel 22, the maincontrol unit 11 is interlocked as shown in FIG. 13 for preventing theoperation for the processing unit from being performed by the maincontrol unit 11.

Thus, during an automatic operation for processing wafers, an operationcan be carried out for performing secondary processing using aprocessing unit not used in the main wafer processing or of actuatingthe processing unit.

The present invention is particularly effective in the case where aprocessing unit is made inoperable because of a failure or the likemidway in the operation; the case where automatic operation is startedin a state where there exists a processing unit required to be subjectedto repair or maintenance at the time of start of operation; and the casewhere, during an operation by operable processing units without use of adiscontinued processing unit, the operation of the discontinuedprocessing unit is re-started. Specifically, according to the vacuumprocessing system of the present invention, including a plurality ofwafer processing units and a wafer transferring unit, even when any oneof the processing units becomes inoperable because of a failure, theoperation can be continued; and even when a processing unit requiresrepair or maintenance upon start of operation, operation can beperformed using operable processing units. This makes it possible toincrease the working efficiency. According to the vacuum processingsystem, moreover, in the case where the recovery of an abnormalprocessing unit or periodic maintenance work is performed on the side ofapparatuses of the processing unit simultaneously with the usualoperation of normally processing wafers, an operator will not sufferfrom a processing gas flowing due to an improper operation and/or anelectric shock due to erroneous turn-on of a discharging power supply.This makes it possible to secure the safety of the operator.

1. A vacuum processing apparatus comprising: first and second processingunits for applying a same processing to a wafer; a lock chamber which ischangeable between a vacuum atmosphere and an atmospheric-airatmosphere; a vacuum transfer unit having a robot disposed between thelock chamber and each of the first and second processing units fortransferring wafers therebetween: an atmospheric transfer unit disposedbetween said lock chamber and an atmospheric carrier for deliveringwafers contained in each of first and second cassettes which aremountable in the atmospheric carrier from a respective cassette to arespective one of the first and second processing units and forreturning the processed wafers to the respective cassette from which thewafer was delivered; and a control unit for connecting transfer controlincluding (1) transferring respective ones of wafers delivered from thefirst cassette to the first processing unit through the lock chamber oneby one using the atmospheric transfer unit and the vacuum transfer unitso as to process the wafers in a vacuum atmosphere, wherein each of thewafers contained in the first cassette is applied with processing by thefirst processing unit in the vacuum atmosphere, and after completion ofprocessing in the first processing unit returning the respectiveprocessed wafers to the first cassette, and (2) transferring respectiveones of the wafers delivered from the second cassette to the secondprocessing unit through the lock chamber one by one using theatmospheric transfer unit and the vacuum transfer unit so as to processthe wafers in a vacuum atmosphere, wherein each of the wafers containedin the second cassette is applied with same processing in the secondprocessing unit in the vacuum atmosphere the processing applied by thefirst processing unit to the wafer contained in the first cassette, andafter completion of processing in the second processing unit returningthe respective processed wafers to the second cassette; wherein thecontrol unit controls completing of transferring and processing for allof the wafers of one of the first cassette and the second cassette,transferring and processing of respective wafers of an other of thefirst cassette and the second cassette at least until exchange of theone of the first cassette and the second cassette in the atmosphericcarrier, and continuing of the same processing.
 2. A vacuum processingapparatus according to claim 1, wherein the processing of the wafers ineach of he first and second processing units is effected substantiallysimultaneously.
 3. A vacuum processing apparatus according to claim 1,wherein each of the first and second processing units include at leastfirst and second processing chambers, and the control unit enablestransfer of a respective wafer from the first processing chamber of arespective processing unit to the second processing chamber of theprocessing unit through the lock chamber one by one using theatmospheric transfer unit and the vacuum transfer unit to completeprocessing of the wafer by the processing unit.
 4. A vacuum processingapparatus according to claim 1, wherein the transfer control unitenables wafers to be alternately delivered from the first and secondcassettes to the respective processing unit.
 5. A vacuum processingmethod for a vacuum processing apparatus having first and secondprocessing units for applying a same processing to a wafer, a lockchamber which is changeable between a vacuum atmosphere and anatmospheric-air atmosphere, and a vacuum transfer unit having a robotdisposed between the lock chamber and each of the first and secondprocessing units for transferring wafers therebetween; comprising thesteps of: delivering by an atmospheric transfer unit wafers contained ineach of first and second cassettes which are mountable in an atmosphericcarrier from a respective cassette to a respective one of the first andsecond processing units through the lock chamber using the atmospherictransfer unit and the vacuum transfer unit, and for returning theprocessed wafers to the respective cassette from which the wafer wasdelivered; controlling transfer of the wafers so as to (1) transferrespective ones of wafers delivered from the first cassette to the firstprocessing unit through the lock chamber one by one using theatmospheric transfer unit end the vacuum transfer unit for processingthe wafer in a vacuum atmosphere, herein each of the wafers contained inthe first cassette is applied with processing by the first processingunit in the vacuum atmosphere, and after completion of processing in thefirst processing unit returning the respective processed wafers to thefirst cassette, and (2) to transfer respective ones of the wafersdelivered from the second cassette to the second processing unit throughthe lock by one using the atmospheric transfer unit and the vacuumtransfer unit so as to process the wafers in a vacuum atmosphere,wherein each of the wafers contained in the second cassette is appliedwith same processing in the second processing unit in the vacuumatmosphere as the processing applied by the first processing unit to thewafer contained in the first cassette, and after completion ofprocessing in the second processing unit returning the respectiveprocessed wafers to the second cassette; and further controllingcompleting of transferring and processing for all of the wafers of oneof the first cassette and the second cassette, transferring andprocessing of respective wafers of an other of the first cassette andthe second cassette at least until exchange of the one of the firstcassette and the second cassette in the atmospheric carrier, andcontinuing of the same processing.
 6. A vacuum processing methodaccording to claim 5, wherein the processing of the wafers in each ofthe first and second processing units is effected substantiallysimultaneously.
 7. A vacuum processing method according to claim 5,wherein each of the first and second processing unit include at leastfirst and second processing chamber, and the step of controlling enablestransfer of a respective wafer from the first processing chamber of arespective processing unit to the second processing chamber of theprocessing unit through the lock chamber one by one using theatmospheric transfer unit and the vacuum transfer unit to completeprocessing of the wafer by the processing unit.
 8. A vacuum processingmethod according to claim 5, wherein the atmospheric carrier is providedfor mounting the first and second cassettes.
 9. A vacuum processingmethod according to claim 5, wherein the step of controlling enableswafers to be alternately delivered from the first and second cassettesto the respective unit.
 10. A vacuum processing apparatus comprising:first and second processing units for applying a same processing to awafer; a lock chamber which is changeable between a vacuum atmosphereand an atmospheric-air atmosphere; a vacuum transfer unit having a robotdisposed between the lock chamber and each of the first and secondprocessing units for transferring wafers therebetween; an atmospherictransfer unit disposed between the lock chamber and an atmosphericcarrier for delivering wafers contained in each of first and secondcassettes which are mountable in the atmospheric carrier from aperspective cassette to a respective one of the first and secondprocessing units and for returning the processed wafers to therespective cassette from which the wafer was delivered; and a controlunit for conducting transfer control including (1) transferringrespective ones of wafers delivered from the first cassette to the firstprocessing unit through the lock chamber one by one using theatmospheric transfer unit and the vacuum transfer unit so as the processthe wafers in a vacuum atmosphere, wherein each of the wafers containedin the first cassette is applied with processing by the first processingunit the vacuum atmosphere, and after completion of processing in thefirst processing unit returning the respective processed wafers to thefirst cassette, and (2) transferring respective ones of the wafersdelivered from the second cassette to the second processing unit throughthe lock chamber one by one using the atmospheric transfer unit and thevacuum transfer unit so as to process the wafers in a vacuum atmosphere,wherein each of the wafers contained in the second cassette is appliedwith same processing in the second processing unit in the vacuumatmosphere the processing applied by the first processing unit to thewafer contained in the first cassette, and after completion ofprocessing in the second processing unit returning the respectiveprocessed wafers to the second cassette; wherein the control unitcontrols interrupting of transferring of respective ones of wafers fromthe first cassette when stoppage of operation of the first processingunit is provided, continuing of the transferring of respective wafersfrom the second cassette, and continuing of the same processing with thesecond processing unit.
 11. A vacuum processing apparatus according toclaim 10, wherein the processing of the wafers in each of the first andsecond processing units is effected substantially simultaneously.
 12. Avacuum processing apparatus according to claim 10, wherein each of thefirst and second processing unit include at least first and secondprocessing chambers, and the control unit enables transfer of arespective wafer from the first processing chamber of a respectiveprocessing unit to the second processing chamber of the processing unitthrough the lock chamber one by one using the atmospheric transfer unitand the vacuum transfer unit to complete processing of the wafer by theprocessing unit.
 13. A vacuum processing apparatus according to claim10, wherein the transfer control unit enables wafers to be alternatelydelivered from the first and second cassette to the respectiveprocessing unit.
 14. A vacuum processing method for a vacuum processingapparatus having first and second processing units for applying a sameprocessing to a wafer, chamber which is changeable between a vacuumatmosphere and an atmospheric-air atmosphere, and a vacuum transfer unithaving a robot disposed between the lock chamber and each of the firstand second processing units for transferring wafers there between;comprising the steps of: delivering by an atmospheric transfer unitwafers contained in each of first and second cassettes which aremountable in an atmospheric carrier from a respective cassette to arespective one of the first and second processing units, and forreturning the processed wafers to the respective cassette from which thewafer was delivered through the lock chamber using the transfer unit andthe vacuum transfer unit; controlling transfer of the wafers so as to(1) transfer respective ones of wafers delivered from the first cassetteto the first processing unit through the lock chamber one by one usingthe atmospheric transfer unit and the vacuum transfer unit forprocessing the wafers in a vacuum atmosphere, wherein each of the waferscontained in the first cassette is applied with processing by the firstprocessing unit in the vacuum atmosphere, and after completion ofprocessing in the first processing unit returning the respectiveprocessed wafers to the first cassette through the lock chamber one byone, and (2) to transfer respective ones of the wafers delivered fromthe second cassette to the second processing unit through the lockchamber one by one using the atmospheric transfer unit and the vacuumtransfer unit so as to process the wafers in a vacuum atmosphere,wherein each of the wafers contained in the second cassette is appliedwith same processing in the second processing unit in the vacuumatmosphere as the processing applied by the first processing unit to thewafer contained in the first cassette, and after completion ofprocessing in the second processing unit returning the respectiveprocessed wafers to the second cassette through the lock chamber; andfurther controlling interrupting of transferring of respective ones ofwafers from the first cassette when stoppage of operation of the firstprocessing unit is provided, continuing the transferring of respectivewafers from the second cassette, and continuing the same processing withthe second processing unit.
 15. A vacuum processing method according toclaim 14, wherein the processing of the wafers in each of the first andsecond processing units is effected substantially simultaneously.
 16. Avacuum processing method according to claim 14, wherein each of thefirst and second processing unit include at least first and secondprocessing chambers, and the step of controlling enables transfer of arespective wafer from the first processing chamber of a respectiveprocessing unit to the second processing chamber of the processing unitthrough the lock chamber one by one using said atmospheric transfer unitand the vacuum transfer unit to complete processing of the wafer by theprocessing unit.
 17. A vacuum processing method according the claim 14,wherein the atmospheric carrier is provided for mounting the first andsecond cassettes.
 18. A vacuum processing method according to claim 14,wherein the step of controlling enables wafers to be alternatelydelivered from the first and second cassettes to the respectiveprocessing unit.